Pressure switch



March 1 19 27.

C. P. EISENHAUER PRESSURE SWITCH Filed Dec. 5, 1925 a o 19 z 0 c z 20 /7 a: L

5 Z I I 25 4043 INVENTOR CHARLES BESENHHUER,

A TTORNE Y5.

UNITED STATES PATENT OFFICE.

cnnnns r. EISEN'HAUER, or DAYTON, OHIO, assrqnon TO THE mmo oomrm, or Barron, 01:10, A CORPORATION or OHIO.

PRESSURE SWITCH.

Application filed December 5, 1925. Serial No. 73,355.

My invention relates to pressure switches.

It is the object of my invention to provide a pressure switch in which the pressure for actuatin the switch in one direction during one portlon of the movement of the switch will be greater than in the other direction,

It is my object to providea pressure-operated switch which will have a cooperating yielding means of difi'erent characteristics for giving a different resistance in different operationsof the switch stroke.

It is a further object to provide a switch of the pressure type which is adapted to make and break electrical contact depending upon the pressure exerted thereon, and depending upon the resistance imparted to the switch, which, in turn, depends upon the operation of the stroke in which the resistance is supplied.

Referring to the drawings-1' Figure 1 is asection through the switch; Figure 2'is a plan view of the switch.

' With reference to the drawings in detail, 1 is a passageway for the introduction of the gas, which is under pressure and which is introduced through the usual pipe line coupled by an internally-threaded. sleeve mounted at 2 on the sleeve 3 of the end 4 of the switch. This end 4 is mounted. on the switch chamber 5 by the screws 6- and is welded thereto by the gasket 7.

On this end wall 4 is mounted a metal bellows 8 which is connected at its free end to a cup 9cthat is, in turn, attached to the plunger 10. The gas is contained within the passageway 1 and the chamber 11 formed by the wall 4:, the bellows 8 and the cup 9. The variation in pressure in this chamber will actuate the plunger 10. The plunger is supported in the bearing sleeve 12 which,;in turn, is threaded within a tubular portion" 13 of the cup 5. Within this bearing sleeve 12 is a helical spring abutting against it, which is designated 14. The other end of this helical spring fits against a collar 15 which is held on the other side by an annular internally-extending ring 16 formed on the insideof the sleeve 17 A groove 18 is formed on. the plunger 10 in which is carried a ring 19. This ring 19 abuts against a second loose collar 20 carried on the shaft, Oneside of which engages with the annular ring 16 and the ring 19, and the other side of which engages with a relatively heavy helical spring 21. The other- This groove is engaged freely by a depending arm 27 pivoted at 28 on a bracket 29 and .forming one arm of a bell crank, the

other arm of which is designated 30. The I arm 30 terminates in a jaw 31 between the arms of which transversely is projected a pin 32 carried on a lever 33 ivoted at 34 on a bracket 35. This bracket is carried on the sleeve 17. The'other end of this lever 33 has pivoted thereto at 36 a plunger 37. This plunger is surrounded by a small helical spring 38, one end of which engages with a shoulder 39 on the plunger, and the other end of which engages within a right angle projection 40 through which the pin 37 rojects. This right angle projection 40 is ormedas a part of the plate 41 pivoted on the bracket 35 at 42. Thus, this plate is carried up or down and serves as a contact plate for engaging with a contact head 43 on a cable 44. i

When the pressure is applied in the chamber 11, the plunger 10' is carried forward with the ring 19 which picks up the ring 20 and operates against the pressure of the heavy helical spring 21.

When this resistance is overcome, the bell crank is operated, the lever 33 is moved about its pivot 34 and the contact plate 41 engages with the contact head 43 closing the circuit of the motor which serves to change, through suitable mechanism, such as a pump, the condition of pressure in the chamber 11.

When this pressure condition is changed to a suitable degree, the spring 21 returns the plunger 10 to-a point where the ring 20 engages the shoulder 16 where it ceases to function and the further movement of the plunger is against the resistance of the relatively light spring 14 which is caused to be compressed by the movement of the plunger with the ring 19 working against the collar which has now been picked up by the ring 19.

The reduction of pressure in the chamber 11 as a result thereof permits the plunger 10 to move toward the bellows end to such an extent that the bell crank will be operated and the circuit broken, thus cutting ofil the motor.

The light spring 14 resists this movement toward the bellows end of the plunger 10 in order that the metal bellows 8 shall not be unduly compressed.

It will be understood that this switch is adapted in a typical installation to work on six inches of vacuum and eighteen pounds of pressure.

It will be understood that I desire to comprehend within my invention such modifications as may be necessary to adapt it to varying conditions and uses.

Havin thus fully described my invention, what I c aim as new and desire to secure by Letters Patent, is

1. In a pressure switch, a pressure chamber, a plunger moved thereby, and a switch adapted to control means for regulating the pressure in the pressure chamber operated y said plunger, yielding means on either side of a shoulder on said plunger, a shoulder on said plunger, said yielding means being adapted to be actuated when the shoulder passes the neutral point of rest of said plunger, said springs being adapted to resist the closing of the switch in one direction and to resist the compression of the pressure chamber in the other direction.

2. In a pressure switch, a pressure chamber, a plunger moved thereby, and a switch adapted to control means for regulating the pressure in the pressure chamber operated by said plunger, yielding means on either side of a shoulder on said plunger, a shoulder on said plunger, said yielding means being adapted to be actuated when the shoulder passes the neutral point of rest on said plunger, said springs being adapted to resist the compression of the pressure chamber in the othervdirection, yielding means resisting the increase of pressure in the pressure chamber being heavier than the yielding means resisting the collapse of the pressure chamber due. to the vacuum.

3. In a pressure switch, a pressure chamber having fixed ends and collapsible walls, a plunger attached to one. of said ends, a switch actuated by said plunger for controlling the operation of apparatus to vary the pressure in the pressure chamber, and yielding means to resist the movement of the plunger in either direction from the normal condition of the plunger and the pressure chamber, said yielding means for resisting the closing of the switch due to the expansion of the pressure chamber under pressure being greater than the resistance to the collapse of the pressure chamber and the opening of the switch.

4. In a pressure switch, a housing, a sleeve for said housing, said housing being formed into a cup, a wall mounted on said cup to close it, said wall having a passageway for the introduction of pressure or the creation of a vacuum, a second chamber formed within the first chamber in the cup having a collapsible wall, one end of which abuts against the cover of the cup and the other end of which is attached to a head mounted on a plunger, a head, a plunger adapted to reciprocate in said sleeve, means for guiding said plunger in said sleeve, yielding means surrounding said plunger, the free ends of which engage the means for supporting the plunger, and the other ends of which engage sliding collars on said plunger, sliding collars and a shoulder on said plunger for engaging said collars alternately, and a shoulder on the interior of said sleeve for limiting the movement of said yielding means, and a switch connected to the end of said plunger adapted to be operated thereby.

5. In a pressure switch, a pressure chamber having a collapsible wall and a movable end, a plunger connected to the movable end, yielding means alternately compressed bly said plunger, means on said plunger for a ternately engaging with said yielding means, and a switch adapted to be operated by said plunger, said yielding means being of greater strength to resist the movement of the plunger when ressure increases in the pressure chamber t an the yielding means which resist the movement of the switch when a vacuum is created in the pressure chamber.

6. In a pressure switch, a casing formed like a cup having a tubular member communicating therewith, a cover for said cup having a passageway therein communicating with a pressure chamber formed within said cup, a metal bellows wall for said pressure chamber, a head carried on said wall" for moving therewith, a plunger connected to said head, caps threaded in either end of said tubular member adapted to support said plunger, a fixed ring carried on said plunger, loose rings carried on said plunger on either side of the fixed ring, helical springs adapted to be engaged by said loose rings, their free ends resting in said cups threaded in the tubular member, a bell crank having one arm connected to said plunger, and the other end to a switch, a switch, and yielding means adapted to snap said switch into and out of operative position.

7. In a pressure switch, a switch controlling a circuit, a bellows communicating with the pressure line, a plunger connected to the bellows, yielding means cooperating with said plunger to resist its movement in either direction, means to independently adjust the fixed abutment and a stop adapted to engage said sliding abutments but not to engage the fixed abutment on the plunger.

- In testimony whereof, I a-fiix my signature.

. CHARLES P, EiSENHAUER. 

